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Topic: 3d printing (Read 4811 times)

Half-related to keyboards... Thinking about getting a 3d printer to print prototype cases/plates but I don't really know which one to get. I've heard the mk3 is great or monoprice mini. What printers do you guys have?

@tp I can see your points, I really just want to be able to make fun layouts on the cheap that don't feel 100% cheap. Sure I could cut out switch holes in cardboard or do it by hand in some other hacky way but 3d printing seems to have some pretty good results based off what I've seen online. I like exploring what I want in a keyboard layout as opposed to the final product sometimes. There are a lot of gb/ic for layouts that are standardized at this point. Doing new ones could be interesting. Maybe I'm not experienced enough and looked into it far enough though. I'm definitely not at the stage of trying to mill them in aluminum yet. Don't have the connections.

@majorkoos I'm ok with gluing things together. I don't have the $ to buy a huge 3d printer or anything. A couple of pieces couldn't hurt. A CNC mill would be amazing to work with but again, funds aren't exactly up there where I can toss a couple thousand away on a hobby.

I work in "the industry" and have designed and built many printers (years of experience with them), and one of a few who have built what are called large format printers.

You need to first understand, a 3d printer is not a toaster. Yes, you know it means you cannot just press a button, but most fail to grasp the learning curve involved and the shear amount of troubleshooting and maintenance involved. They are literally a hobby unto themselves and people REALLY do not understand that. These have FAR more in common with a CNC mill than they do printing or even woodworking, that includes the amount of trouble they can cause and the skill required to get good prints from them.

Also, I don't know what size keyboard you are working with, but anything over 60% gets sketchy on most printers, I built my first big one (several years ago) to handle a TKL laid flat and it's still one of the largest around. Another thing people forget with large printers is that they need a lot of space... LOTS of space. I have found peoples eyes are very much larger than their desk. Mine barely fits on my desk, and any larger it would require a dinner table to support it. No big deal you say, but it's not like you can just put it in a closet when not in use, this is a big machine.

Anyhow...Chinese printers are exactly what you would imagine. Some are okay, some are pretty good, however, MOST are designed by someone and run though a couple prints and sent off to manufacturing. Worse, of the ones I have seen, most arrived with at least one part being broken. Granted, that is one reason it was brought to my attention so I could help fix it, but I'm not alone in this and I was far from impressed with parts quality on the cheaper ones. Even the better ones almost always need work to make them work well.

Some have even shocked people, and some simply didn't even function out of the box. 3d printing became a race to the bottom, and all rules for quality went out the window. Bigger printers are no exception. They also have HORRIBLE support.

At TP mentioned, they are often warped. Even under the best circumstance, something thin and flat will have some twist. You need structure to flatten it back out (I.E. a case). This is especially true with plastics like ABS. Plastic shrinks as it cools, some by a little (approx. PLA 0.3%) and some by a lot (ABS 3-7%). This causes prints to shrink and warp, but it also causes the plastic to pull itself off the bed. Some of the plastics are also toxic (ABS and some nylons in particular) and should not be used without a fume extractor, some are safe (PLA), for the most part. Some, like ABS are also EXTREMELY sensitive, people erect cardboard walls around printers because simply opening a door can cause a draft that causes it to delaminate. No, I'm not joking, ABS is a nightmare for many printers. You need an enclosed printer to really do ABS and you still have shrinkage and warping.

As for a printer, the Prusa I3 is about the cheapest you really want to go. Some will argue some of the clones are better, frankly, no. Yes, these is a few good clones for less, but they lack the support you need as someone new to the hobby, yes hobby. The Prusa has features that will greatly improve the likelihood of a good print and their support system is excellent. It also prints good, where I think it fails is in longevity, it has wear issues some other designs do not have, however every design has tradeoffs. This is not a slam on Prusa, it's one of the few printers I will recommend to people, and certainly one of the cheapest. If you had some experience, one of the clones could be a bargain, but if you are just starting and do not have access to help locally, the Prusa is the cheapest good option. You may say I can just work through it, and this is true, but do you want to have a working plate next week, or are you willing to spend the next 2 months learning before you get a good, usable print and what is it worth to you?

Lastly...A 3d printed prototype is great, it can find flaws quickly and help you correct them, cheaply. However... Your 3d printer does not have the same tolerances as a laser, water jet, or cnc mill. So, even if you get everything right on the printer, it does not mean it will translate to the other formats. It can reduce the time and prototypes required, but do not expect it to come out perfect just because you tested it on a 3d printer first. At least not without some experience.

So here is my advice.If you want to play, and make a case, get a printer, but don't expect a working, functional item right away. This is engineering. While a plate may seem simple, it's a whole other aspect when you have to concern yourself with shrinkage, warpage, tolerances, along with making sure your temps are right, extruder didn't jam, did something come loose.... Talk to many people with them, and unless you get a high end kit, it could be months and several kilos of plastic before you get anything remotely useful.

If you just want a plate and want it cheap, take it to a laser cutter or waterjet and just get it done, a few prototypes should give you all you need before a final product is made and those will likely be less than the cost of a decent 3d printer. If you plan on manufacturing it, make it clear to them that there will be a bulk purchase once completed, you will get it faster, they will often make suggestions on how to make it cheaper and often charge you less for the prototypes (but don't lie!). Remember, making stuff on a 3d printer is cheap, but only if you already own it.

I see alot of these budget machines use plastic couplings or all plastic bodies..

That's just not conducive to precision across a long-print.

I own both mixed and all metal, the larger you go, the more metal you want, but for a printer for home use, it's far from a problem.

Metal stretches and shrinks based on temp, while plastic parts, as has been seen in cell phones, plastic is forgiving (ask Iphone users why they have a case). You can bump it, bash it, dent it and it can maintain it's shape (and often calibration), while metal will permanently deform or need to be unbolted and straightened up again.

I have two anet a8 printers that I use primarily for printing out dnd terrain and movie props. I will say that although you can pick up two for under 400 dollars I wouldn't if you value your time and sanity. While yes, the print quality CAN be pretty good, the amount of time I have spent tweaking, upgrading and completely dissembling both printers has been a hassle to say the least. At least one is down at any given time, and because I print quite a lot the entire thing is pretty frustrating. If I could do it all again I would go with a prusa and probably will get an mk3 kit sometime in the near future. I've heard nothing but great things about it.

I think there is also an overestimation of final aesthetics with 3D prints. Ordering from a professional printer like Shapeways can yield beautiful results, but those machines are tens (if not hundreds) of thousands of dollars. I've had 3D prints done for me with a $500 printer and the quality just isn't there for highly detailed items.

I think there is also an overestimation of final aesthetics with 3D prints. Ordering from a professional printer like Shapeways can yield beautiful results, but those machines are tens (if not hundreds) of thousands of dollars. I've had 3D prints done for me with a $500 printer and the quality just isn't there for highly detailed items.

TLDR - you can't print artisan quality caps on a FDM printer. Get a DLP or SLA resin printer for that.

I think there is also an overestimation of final aesthetics with 3D prints. Ordering from a professional printer like Shapeways can yield beautiful results, but those machines are tens (if not hundreds) of thousands of dollars. I've had 3D prints done for me with a $500 printer and the quality just isn't there for highly detailed items.

You'd be surprised.

When you contract an SLA or SLS printer, layer heights are 0.01mm, however an FDM is usually quoted at 0.2mm (and 20 or 25% infill). which, personally, is garbage quality. You can ask for smaller layers, even a cheap FDM should be capable of 0.1mm or even 0.8mm, but a good one (Lullzbot, Ultimaker, Prusa, etc.) can get down to 0.05 or even lower. My FDM printers have been down to 0.01mm layer height, same as SLS and SLA and the surface finish was as smooth as glass.

However... It took FOREVER.A print that would take 5 minutes at 0.1mm now needs 100x more layers, that 5 minutes just became 500 minutes, over 8 hours of print time for something you did in 5 minutes. Now on a nice machine, that's fine and you need a REALLY nice machine to hit that layer height, but a 5 minute print at 0.1mm is a TINY object, like a 1/4in cube. Try printing something more substantial that would normally take 8 hours and now you are looking at 800 hours, on a good printer.

A cheap printer like an Anet would need closer to 1200 hours, not that it's even capable of doing a 0.01mm, but from what I've seen, I'm not sure if most of these cheap printers can even go 1200 hours without a serious problem cropping up, even with regular maintenance along the way (which will be significant). Some of these cheap Kickstarter printers will not even last that long... Looking at you Tico!

I think there is also an overestimation of final aesthetics with 3D prints. Ordering from a professional printer like Shapeways can yield beautiful results, but those machines are tens (if not hundreds) of thousands of dollars. I've had 3D prints done for me with a $500 printer and the quality just isn't there for highly detailed items.

You'd be surprised.

When you contract an SLA or SLS printer, layer heights are 0.01mm, however an FDM is usually quoted at 0.2mm (and 20 or 25% infill). which, personally, is garbage quality. You can ask for smaller layers, even a cheap FDM should be capable of 0.1mm or even 0.8mm, but a good one (Lullzbot, Ultimaker, Prusa, etc.) can get down to 0.05 or even lower. My FDM printers have been down to 0.01mm layer height, same as SLS and SLA and the surface finish was as smooth as glass.

However... It took FOREVER.A print that would take 5 minutes at 0.1mm now needs 100x more layers, that 5 minutes just became 500 minutes, over 8 hours of print time for something you did in 5 minutes. Now on a nice machine, that's fine and you need a REALLY nice machine to hit that layer height, but a 5 minute print at 0.1mm is a TINY object, like a 1/4in cube. Try printing something more substantial that would normally take 8 hours and now you are looking at 800 hours, on a good printer.

A cheap printer like an Anet would need closer to 1200 hours, not that it's even capable of doing a 0.01mm, but from what I've seen, I'm not sure if most of these cheap printers can even go 1200 hours without a serious problem cropping up, even with regular maintenance along the way (which will be significant). Some of these cheap Kickstarter printers will not even last that long... Looking at you Tico!

I tried 0.04mm layers using a 0.15mm nozzle (Ultimaker 2+) and it took most of the day to print a single keycap.I also needed to add a sacrificial print to the job to give the print enough time to cool between layers.For keycaps a $500 DLS resin printer will provide much better results IMO.For cases it's more about build volume than accuracy so FDM works well.

Should be pretty straight forward.. one motor good to go probably has to gear down though since microsteps arn't accurate, or maybe a servo kit. .. Do they use 4k projectors for these yet ?

Gearing down is easy.ACME 8mm threaded rod, 400step 1/32nd motors and 2:1 gear ratio belt drive will get you down to 0.01mm exactly. However, at that point the system can't even move more than about 4.5mm per second it's geared so low (3200 steps per/mm). Unfortunately, each microstep would be exactly 0.01mm , meaning if you are off by 0.002 you have no way to correct, so I would consider using an 8:1 or even 10:1 gear reduction. Of course, raising and lowering the z would be painfully slow. Which makes me wonder about some of these cheap resin printers as to what their ratio and layer height limits really are or if they are just rolling with it.

As for 4k, there's the screen method, which is faster (sort of) but has a downside of you need a screen bright enough ($$$) and in a small enough size. As you go up in screen size, your resolution actually drops. Using a projector solves most of the brightness, but messes with focus and scale, also $$$. The other method is dragging a laser around underneath, this allows any size you want, while slower, it retains it's resolution and is cheaper, especially for larger build volumes.

The screen methods also need special and more sensitive resin, which can flash off when exposed to ambient light, even while sitting in the tray. Using the laser you have a larger selection of available resins you can use, which are less fickle, however you have to take precautions because of the laser.

If you want something small, the screens are a cheap way to go, but these ramp up fast in price. The same applies to projectors, have you looked at what a high output 4k projectors costs?

Honestly, I haven't really but a lot of effort into this because I'm just not sure I want to go resin yet.. Resin is REALLY, REALLY messy, it also smells. You almost need a dedicated room with ventilation and clean up area, then there is the cost to feed it, not only does it cost more, but the resins also have a limited life. They just are not good for home use. Resin is kind of like an inkjet printer, you gotta use it enough to keep things from just going to waste, but use it a lot and it can eat you out of house and home.